Adjustable gastric banding apparatus have provided an effective and substantially less invasive alternative to gastric bypass surgery and other conventional surgical weight loss procedures. Despite the positive outcomes of invasive weight loss procedures, such as gastric bypass surgery, it has been recognized that sustained weight loss can be achieved through a laparoscopically-placed gastric band, for example, the LAP-BAND® (Allergan, Inc., Irvine, Calif.) gastric band or the LAP-BAND AP® (Allergan, Inc., Irvine, Calif.) gastric band. Generally, gastric bands are placed about the fundus, or cardia, or esophageal junction, of a patient's upper stomach forming a stoma that restricts food's passage into a lower portion of the stomach. When the stoma is of an appropriate size that is restricted by a gastric band, the food held in the upper portion of the stomach may provide a feeling of satiety or fullness that discourages overeating. Unlike gastric bypass procedures, gastric band apparatus are reversible and require no permanent modification to the gastrointestinal tract. An example of a gastric banding system is disclosed in Roslin, et al., U.S. Patent Pub. No. 2006/0235448, the entire disclosure of which is incorporated herein by this specific reference.
Existing gastric bands periodically require adjustments to maintain an effective constriction about the stomach, to account for changes in the stomach tissue, reduction of fat or other factors causing movement and/or size change of the stomach. Some attempts have been made to allow for such adjustment of gastric bands. For example, hydraulic gastric bands utilize a fluid such as saline to fill an inflatable portion of the gastric band using a subcutaneous injection port. Adjustments to the amount of inflation may be made by injecting or extracting the fluid through the patient's skin into or out of the injection port, which then directs the fluid into or out of the inflatable portion of the gastric band.
Current injection ports are typically designed to include complicated and/or intricate solid compressing geometries which may reduce functional performance and/or increase cost.
For example, with reference to FIGS. 1A and 1B, Redmond, et al., U.S. Pat. No. 4,781,680, discloses an injection port having a plurality of inter-related components including a filter element and a cup-shaped compression member, among other components.
With reference to FIG. 2, Johnston, et al., U.S. Pat. No. 4,886,501 discloses a low-acute angle implantable device having a septum axially aligned with a connector.
With reference to FIG. 3, Fogarty, et al., U.S. Pat. No. 6,039,712, discloses an implantable injection port having multiple elastomeric penetrable layers and mesh layers. The mesh layers are for creating fluid channels for the passage of fluids to the tubing port/connector.
Accordingly, in certain embodiments, it may be desirable to develop an injection port being of a simpler assembly, improved reliability, cost savings, needle accessibility and/or sealing functionality of the device, among other benefits.